1. Field of the Invention
This invention relates generally to a system and method for the recovery and reintroduction of atmospheric vented gases and more particularly to the recovery and reintroduction of gases and fluids generally discharged into the environment from hydrocarbon separation systems used in production, process and transmission systems.
2. General Background
Eductors or jet pumps have been in use for many years in different applications as a means of pumping, vacuuming, and mixing in a great many applications. Eductors are simple to build and operate with essentially no mechanical parts to break down. The Eductor operates on the principle of a venturi, through which an energized fluid is directed causing a differential pressure across an orifice situated in a mixing chamber. The mixing chamber has a port to allow fluids or gases at a static or lower pressure than the energizing fluid pressure to be drawn into the chamber due to the created differential between the energized or pressurized line and the static or lower pressure inlet lines. The fluids or gases being drawn into the chamber mix with the energized fluid or gases resulting in a mixture of both fluids and or gases as result of the pressure differential between the energized fluid or gases and the fluid or gas being drawn into the mixing chamber from the static or lower pressure inlet line. The pressure and volume of the mixed fluids may be adjusted by controlling the energized and static inlet fluid volume and pressure with a restricting device installed in the inlet lines to the Eductor. The mixed fluid departs the chamber at a reduced pressure less than the inlet energized fluid, but greater than the static or lower pressure fluid or gas being drawn into the mixing chamber.
Although various systems using such Eductors have been developed for vapor recovery in handling volatile liquids which emit toxic gas, such as those disclosed by U.S. Pat. Nos. 3,817,265, 5,135,360, 5,139,390, 5,195,587, 5,207,249, 5,325,896, 5,651,389 and 5,957,665. Even closed loop systems such as that disclosed by U.S. Pat. No. 5,516,119 have proven effective in controlling gas emission However, Eductors are primarily used as mixing and stripping systems such as is disclosed by U.S. Pat. Nos. 3,648,434 and 5,209,762. Other systems utilize various methods for capturing vapors emitted from gas dehydrators, oil storage tank, and catalytic cracking processes while still others utilize a venturi type apparatus for capturing vapors emitted from gasoline being transferred into tanks.
A system utilizing the eductor, or jet pump, although not new to the art, has not been utilized in the manner taught herein for use in gas/oil production, processing or transmission systems for collectively recovering hydrocarbon fluids and gases, including greenhouse gases such as methane, ethane, and hydrocarbon compounds, VOC's, Volatile Organic Compounds that react and produce ozone in the lower atmosphere, HAP, Hazardous Air Pollutants including benzene, toluene, ethybenzene, xylene, n-hexane, 2-2-4 trimethyl pentane, and CO and NOX, gas produced from combustion and/or released from natural gas, as well as many other air pollutants currently being vented into the atmosphere from the various stages of a hydrocarbon separation processing systems for reinjection and recirculation within the processing system without the use of any external energy or powered mechanical pumps etc. .
Some current systems use compressors to produce condensation for dilution, while others use flares or mix the exhaust gases and fluids with other fuel gases to produce fuel to be burned in engines or heater burners utilized with the hydrocarbon processing system itself . These existing processes create combustion emissions (CO & NOX) themselves which must also be exhausted. In some cases these systems use outside energy sources such as electricity or natural gas to operate and are therefore more costly than the process disclosed herein utilizing the EVRU.
Therefore, there is a need for an efficient, economical system capable of capturing hydrocarbon emissions from the various vented exhaust ports within separation systems used for production, processing and transmission of oil and gas and reintroducing the vented contaminates in a closed loop system back into the system without interrupting or using any additional energy.